(201) Airway Management in an Adult With an Atrial Septal Defect With Severe Pulmonary Hypertension

Introduction: Adults with unrepaired atrial septal defects are at risk of developing significant right sided heart disease due to intracardiac shunting. Pulmonary hypertension and right ventricular (RV) failure poses a challenging clinical dilemma if the need for endotracheal intubation and mechanical ventilation arises. This case describes a patient with severe pulmonary hypertension and RV failure secondary to an unrepaired atrial septal defect (ASD) requiring intubation for hypoxic respiratory failure from septic shock.

Description: A 68 year-old woman with an unrepaired ASD, severe pulmonary hypertension, RV failure, and a chronic large pericardial effusion was admitted with hypoxic respiratory failure, found to have salmonella bacteremia and viral pneumonia secondary to metapneumovirus. She had rapidly escalating oxygen requirements requiring maximal high-flow nasal cannula. Transthoracic echocardiography (TTE) confirmed severe pulmonary hypertension with a pulmonary artery systolic pressure of 80 mmHg, RV failure, and a large pericardial effusion (Figure 1) without evidence of tamponade. She was intubated in the setting of encephalopathy and hypercarbia. Intubation was performed using ketamine for induction and rocuronium for paralysis. Hypotension during intubation was managed with vasopressin and norepinephrine continuous infusions. Mean arterial pressure (MAP) was maintained above mean pulmonary pressure to avoid shunt. Inhaled nitric oxide was added to mitigate the rising pulmonary pressures peri-intubation.

Discussion: In RV failure intubation should be considered only as a last resort due to the potentially catastrophic consequences on RV hemodynamics. Intubation in RV failure threatens to reduce preload by impeding venous return from elevated intrathoracic pressure and increased RV afterload secondary to positive pressure ventilation. This case was complicated by an ASD shunt, which can have preferential right to left shunt under conditions of elevated pulmonary pressures and reduced MAP. This necessitated use of pressors and inhaled nitric oxide. Choice of sedative in this situation should aim to reduce hemodynamic compromise. Ketamine as the induction agent provides catecholamine release and sympathetic stimulation which mitigates some negative hemodynamic effects of intubation.